Compositions for protecting genetically engineered plants from disease and phytotoxic effects of herbicides

ABSTRACT

Compositions and methods providing herbicidal, fungicidal and/or nutritional activity to genetically engineered crops in a single application are disclosed. The composition comprises an aqueous mixture of glyphosate salt and phosphite at a molar ratio of about 1:2 to about 4:1 glyphosate salt to phosphite; wherein the composition is formulated as a liquid for dilution to an application rate of the dissolved glyphosate salt of between about 0.47 pounds per acre and about 4.13 pounds per acre.

FIELD OF THE INVENTION

The present disclosure relates to compositions that protect crops of genetically engineered plants from the phytotoxic effects of herbicides, such as, glyphosates, that are applied to these crops for the reduction of growth of unwanted vegetation; thereby, mitigating damage to the non-target plants.

BACKGROUND OF THE INVENTION

Various elemental Phosphorus (P) derivatives and methods are, known in the chemical art as “glyphosates”, which are effective and commercially important broad spectrum herbicides useful in controlling the growth of geminating seeds, emerging seedlings, maturing and established woody and herbaceous vegetation and aquatic plants.

Glyphosates are used as post-emergent herbicides to control the growth of a wide variety of weed species in crops and are the active ingredient in the “ROUNDUP” family of herbicides available from Monsanto Company St. Louis, Mo. Glyphosates have been widely used in agriculture for many years and the preparation and use thereof are disclosed in U.S. Pat. Nos. 3,853,530 and 3,977,860.

Beneficial plants have been genetically engineered to resist or tolerate glyphosates and crops of such plants are treated with glyphosates usually by spray application to reduce or eliminate adjoining weeds and other harmful vegetation which reduce crop yields.

Advances in genetic engineering have transformed cultivated crops, such as, soybeans, maize (corn), sorghum, canola, alfalfa, cotton and wheat to provide tolerance to glyphosate herbicides, also known as “ROUNDUP READY” crops.

Glyphosate resistant or tolerant crops reduce the need for tillage for weed control thereby reducing soil erosion and lowering crop production costs (fuel and labor) involved in tillage. However, for many crops, the genetically induced resistance is not completely total, and the application (usually foliar) of the glyphosate, can result in yield losses since the crop may also be adversely affected, either mildly or greatly, by the herbicide application. Depending on other adverse factors of production, such as, soil conditions, climate, disease, insect pressure, inadequate plant nutrition, or other factors, the crop can itself be temporarily stunted from the herbicide application and suffer a “set back”, or “yield drag” from which it takes time to recover.

As used herein, the term “yield drag” is defined as the decrease in crop yield as a result of applying increasing rates of a glyphosate herbicide such as Roundup to genetically engineered Roundup Ready crops in order to mitigate weed growth.

As used herein, the term “set back” is defined as the decline in physical appearance and vigor of a genetically engineered Roundup Ready crop resulting from the Roundup application itself.

It is during this recovery period that crops are weakened and vulnerable to other forms of crop reduction pressure, before a return to a normal growth pattern. In many cases the plants may not fully recover which results in a reduced crop yield.

An inadequate method to avoid this “set back” or “yield drag” is to use/prescribe lower rates of glyphosphate so that the adverse effect to the crop is reduced, but this can result in inadequate weed control and the development of glyphosate resistant weed species.

It would be desirable to have a composition that when applied with herbicides would allow genetically engineered crops to avoid such “set back” or “yield drag” losses altogether or at least allow them to recover more quickly after application of glyphosate and other herbicides in order to improve crop yields as well as improve the health of the crop.

It would further be desirable to have a product that can be applied to genetically engineered food crops that will both control undesirable and unwanted vegetation, but also effectively stop, retard, or mitigate fungal and bacterial diseases, and/or insect crop damage, caused by, or exacerbated by foliar herbicide applications.

It would further be desirable to have a product that can be applied together with the glyphosate in order to allow the glyphosate to be applied at full strength in order to control resistant and non-resistant weed species while not harming or reducing the yield of the desirable or planted crop.

SUMMARY OF THE INVENTION

The composition of this invention provides protection against set-back to genetically engineered crops resistant to the effects of a glyphosate herbicide and improves crop yields.

The novel composition of this invention combines salts of glyphosate with a phosphite in effective amounts for foliar application to genetically engineered crops. The effective amount of glyphosate continues to be a weed control composition, while the effective amount of the phosphite eliminates or substantially reduces the set back period of time, allowing crops to meet their genetic growth potential to grow healthier and result in crop yields being higher in a shorter period of time than if a dissolved glyphosate salt solution was applied individually.

The composition of this invention comprises:

(1) glyphosate salt; and,

(2) phosphite wherein the molar ratio of (1) to (2) is about 1:2 to about 4:1, and more preferably, about 1:1 to 2:1 and, where (1) and (2) are provided in a diluted solution in which the amount of glyphosate salt in solution is applied at the rate of about 0.47 lbs/acre to about 4.13 lbs/acre.

In one embodiment of the invention, the glyphosate salt is dissolved to form a concentrated solution or can be purchased in a product such as ROUNDUP POWER MAX®. It is thereafter diluted and the phosphite component is added to the diluted solution prior to foliar application.

Definitions

The term “about” means within 10% of a given value or range.

The term “comprising” is intended to include embodiments encompassed by the terms “consisting essentially of” and “consisting of”. Similarly, the term “consisting essentially of” is intended to include embodiments encompassed by the term “consisting of”.

The term “phosphite” means salts of phosphorous acid, whose mono- and di-basic salts include mono- and di-potassium, mono- and di-sodium, mono- and di-ammonium, or combinations thereof. In addition, phosphorous acid molecules can be joined by a condensation reaction to form a series of polyphosphorous acids, and polyphosphite salts. These polyphosphite salts include mono- and di-potassium, mono- and di-sodium, mono- and di-ammonium.

The term “glyphosate” means salts of N-(phosphonomethyl) glycine such as, ammonium salt, e.g. diammonium salt, amine salt, e.g. isopropyl amine salt, potassium salt, sodium salt, or sulfonium salt, e.g. trimethyl sulfonium salt or combinations thereof.

The term “genetically engineered crops” means crops or plants, such as, soybeans, maize (corn), sorghum, canola, alfalfa, cotton and wheat that have been genetically engineered to provide tolerance to a glyphosate or other herbicides. Crops described as Roundup Ready are included under this term.

Phosphites are effective because they are systemic fungicides which, unlike surface protectant fungicides which can easily wash off the plant surface, can protect plants from diseases during the entire growing season. Phosphites move systemically upward and downward throughout the entire plants vascular system, translocating to the new growth, via both the xylem and the phloem activating the plants own natural, self defense mechanisms, systemic acquired resistance (SAR) and induced resistance (IR).

Calculations are based upon ROUNDUP POWER MAX® which provides 5.5 pounds potassium salt of glyphosate per US gallon. Based on the concentration of glyphosate salt in POWER MAX®, a foliar application of 11 oz/acre of ROUNDUP POWER MAX® equates to 0.47 pounds of glyphosate salt per acre and application of 96 oz/acre equates to 4.13 pounds dissolved glyphosate salt per acre.

Over this range, i.e. 11 oz/acre to about 96 oz/acre, genetically engineered plants are surprisingly tolerant in view of the glyphosate manufacturer's warning not to exceed 44 oz/acre (1.89 lbs/acre). The addition of phosphite to the glyphosate salt solution subsequently diluted and then foliar applied to genetically engineered plants improves the health of the plant while providing effective weed control up to at least six weeks after application.

Delivery of a higher concentration of glyphosate in the form of a glyphosate salt solution means that significant weed development is less likely to occur prior to harvest. It is believed that foliar application of a greater amount of glyphosate salt minimizes the potential that weeds will develop a resistance to treatment as may occur if treatment is delivered in repetitive smaller doses over time. By saving at least one extra trip across the field, the combining of effective amounts of dissolved glyphosate salt and phosphite reduces labor costs and is more environmentally friendly. As mentioned earlier, the glyphosate salt phosphite combination also synergistically reduces yield drag and set back to genetically engineered crops than if a glyphosate salt solution was applied separately. The glyphosate herbicide component provides effective weed control while the phosphite component provides the necessary stimulus to maintain vigorous growth.

The novel composition of glyphosate salt and phosphite can be cold blended with water for application. The composition may also be used in a concentrated form for metering and injection for crop application. Typically, effective amounts are applied to a crop depending on the crop and the result that is required.

The novel composition can be pre-blended for simultaneous application either as a pre-blended stable, clear and sprayable product composition having a relatively long shelf life; or, tank mixed together in the field for application.

In one embodiment, an aqueous potassium polyphosphite solution is the phosphite component prepared by a process set forth in U.S. Pat. No. 7,887,616 and which is hereby incorporated by reference.

Another preferred embodiment is a composition that when applied to genetically engineered crops the composition provides the crops resistance to setback and consists essentially of a glyphosate and a phosphite; wherein the molar ratio of glyphosate to phosphite is about 1:2 to about 4:1, and more preferably, from 1:1 to 2:1 and the concentration range for foliar application of glyphosate salt is between about 0.47 lbs/acre (11 oz/acre) and 4.13 lbs/acre (96 oz/acre).

With respect to the phosphite used, calculations in this specification are based upon a dissolved phosphite solution of KPHITE®, manufactured by Plant Food Systems, Zellwood, Fla. which provides 7.03 pounds of phosphite (mono- and dipotassium salts of phosphorus acid) dissolved in one gallon of liquid.

Any of the embodiments presented herein or made according to our invention can be diluted with water for agricultural treatment of Round-up Ready crops or other genetically engineered crops. Additional nutrients well known in the agriculture industry can also be added to the diluted solution for foliar application.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

By combining phosphite with a salt of glyphosate, “set back” of genetically engineered crops can be substantially reduced or eliminated.

Genetically engineered crops, specifically Roundup Ready corn, cotton and soybeans were seeded in 36″ rows; each row being 60 feet in length. Between each Roundup Ready row was seeded respective rows of Johnsongrass, Sicklepod, Ragweed and Pigweed. The plants were allowed to germinate and the foliar test application began 42 days after planting.

Fifteen separate treatments were applied, three replications per treatment; each treatment covering 3 ft of each row and the treatments were applied perpendicularly across each row. Between each application was a 1 foot spacing to minimize comingling of treatments.

The glyphosate salt used in the testing was a product sold under the trademark ROUNDUP POWER MAX®, a product manufactured by Monsanto Chemical, St. Louis, Mo. The active ingredient was Glyphosate, N (phosphonomethyl) glycine, in the form of its potassium salt making up 48.7% of the solution. ROUNDUP POWER MAX contains 660 grams per liter or 5.5 pounds per US gallon of the active ingredient glyphosate. The application rate of ROUNDUP POWER MAX® was tested at 11 oz, 22 oz, 32 oz, 44 oz, 64 oz and 96 oz/acre diluted with water.

The phosphite component used for testing was a product sold under the trademark KPhite® 7LP, a product manufactured by Plant Food Systems, Inc., Zellwood, MO. The KPhite® product has as active ingredients mono and di potassium phosphite making up about 56.0% of the solution and contains 7.03 pounds per US gallon of the active ingredients.

The phosphite solution was combined with the glyphosate salt solution and applied to the plants at an application rate of 32 oz/acre.

TABLE 1 Roundup Ready Trial (42 day evaluation) Weed Control Crop Treatment Description Effectiveness Appearance 1 11 oz Roundup Power Max 2.5 8 2 11 oz Roundup Power 2.5 10 Max + 32 oz Kphite 3 22 oz Roundup Power Max 4 7 4 22 oz Roundup Power 4 10 Max + 32 oz Kphite 5 32 oz Roundup Power Max 5 6 6 32 oz Roundup Power 5 10 Max + 32 oz Kphite 7 1 qt Kphite 1 10 8 Untreated Check 1 9 9 44 oz Roundup Power Max 6 4 10 44 oz Roundup Power 6 9 Max + 32 oz Kphite 11 64 oz Roundup PowerMax 7 3.5 12 64 oz Roundup Power 7 8 Max + 32 oz Kphite 13 96 oz Roundup Power Max 9 2 14 96 oz Roundup Power 9 7 Max + 32 oz Kphite Rating Scale of 1 to 10 with 1 = Poor and 10 = Excellent

Test Results

42 days following foliar application, the plants were observed. A scale of 1 to 10 was used for rating weed control effectiveness and crop appearance. Both the weed control effectiveness of the foliar application and the crop appearance were visually observed and each assigned a value.

Crop appearance is a visual observation comparing each treatment against how a crop should appear. The phosphite-only treatment had the best appearance, i.e. no set back and no yield drag (Test 7).

The maximum foliar application rate was 96 oz/acre ROUNDUP POWER MAX® (Tests 13 and 14). The appearance of genetically engineered crops were surprisingly healthier when applied in combination with phosphite (Test 14) than crops receiving only the glyphosate salt solution (Test 13). Lower application rates of ROUNDUP (Tests 1, 3, and 5), exhibited noticeable deterioration of crop appearance when compared to the untreated sample (Test 8).

At low concentrations of ROUNDUP (Tests 2, 4, and 6), no set back or yield drag was observed. However, the level of weed control, as expected, greatly improved at the higher application rates of ROUNDUP POWER MAX. The lowest application rate of ROUNDUP POWER MAX (test 1) showed poor weed control and limited crop injury.

From the above testing, the following conclusions are presented:

A. Use of a glyphosate salt solution as a single application causes Roundup Ready Crops to suffer set-back and the degree of set-back is proportional to the concentration applied.

B. The co-application of a glyphosate salt solution and a phosphate component showed surprising and unexpected results. The phosphite component, although applied at a single application rate (32 oz/Acre) had a beneficial effect to genetically engineered crops experiencing no set-back regardless of the dissolved glyphosate salt application rate (11 oz/Acre-96 oz/Acre). 

What is claimed is:
 1. An herbicidal composition for weed control in crops genetically engineered for tolerance to glyphosate and/or other herbicides, comprising glyphosate salt and phosphite; wherein the composition is formulated by combining the glyphosate salt with a phosphite, or with a polyphosphite, or with a combination of phosphite and polyphosphite; wherein the composition is formulated as a liquid for dilution to an application rate of the dissolved glyphosate salt of between about 0.47 pounds per acre and about 4.13 pounds per acre; and wherein the composition is effective in controlling weed growth in the genetically engineered crop while reducing setback or yield drag in the crop to which it is applied, as compared with an equivalent crop treated with an equivalent amount of the glyphosate salt and/or other herbicides, in the absence of the phosphite.
 2. The composition of claim 1, comprising glyphosate salt and at least one other herbicide.
 3. The composition of claim 1 in the form of a concentrate for metering into an aqueous spray for foliar application.
 4. The composition of claim 1 in the form of an aqueous premixed blend for direct foliar application.
 5. The composition of claim 1, wherein the glyphosate salt is selected from a group consisting of ammonium salt, diammonium salt, amine salt, isopropyl amine salt, potassium salt, sodium salt, sulfonium salt, trimethyl sulfonium salt and any combinations thereof.
 6. The composition of claim 1, wherein the phosphite is selected from the group consisting of monopotassium phosphite, dipotassium phosphite, monosodium phosphite, disodium phosphite, monoammonium phosphite, diammonium phosphite, mono-potassium polyphosphite, dipotassium polyphosphite, monosodium polyphosphite, disodium polyphosphite, monoammonium polyphosphite, diammonium polyphosphite and any combination thereof.
 7. A method of controlling weeds in a crop that is genetically engineered for tolerance to glyphosate and/or other herbicides while reducing setback or yield drag in the crop, comprising the steps of: applying a liquid formulation of glyphosate salt to and/or at least one other herbicide to the crop that is genetically engineered for tolerance to glyphosate and/or other herbicides having weeds disposed therein; and applying a liquid formulation of phosphite to the crop that is genetically engineered for tolerance to glyphosate and/or other herbicides having weeds disposed therein; whereby the application of the glyphosate salt and/or the at least one other herbicide and the phosphite results in weed control in the crop while reducing setback or yield drag in the crop, as compared with an equivalent crop treated with an equivalent amount of the glyphosate and/or other herbicides in the absence of the phosphite.
 8. The method of claim 7, wherein the herbicides and the phosphite liquid formulations are mixed together prior to application to the crop.
 9. The method of claim 7, wherein the herbicides and the phosphite are formulated as an aqueous premixed blend for direct foliar application to the crop.
 10. The method of claim 7, wherein the genetically engineered crop is selected from the group consisting of: soy bean, maize, sorghum, canola, alfalfa, cotton and wheat.
 11. The method of claim 7, wherein the glyphosate salt is selected from a group consisting of ammonium salt, diammonium salt, amine salt, isopropyl amine salt, potassium salt, sodium salt, sulfonium salt, trimethyl sulfonium salt and any combinations thereof.
 12. The method of claim 7, wherein the phosphite is phosphorous acid or a salt thereof, or polyphosphorous acid or a salt thereof, or any combination thereof.
 13. The method of claim 12, wherein the phosphite is selected from the group consisting of monopotassium phosphite, dipotassium phosphite, monosodium phosphite, disodium phosphite, monoammonium phosphite, diammonium phosphite, mono-potassium polyphosphite, dipotassium polyphosphite, monosodium polyphosphite, disodium polyphosphite, monoammonium polyphosphite, diammonium polyphosphite and any combination thereof. 